00:01
Hi, in this question we are asked to calculate mass of cf2 -cl2 that is vaporized in refrigerator cycle to convert all the water at 22 degrees celsius to ice at minus 5 degrees celsius.
00:15
We are given with mass of one ice cube that is 30 gram.
00:19
It means the mass of 18 ice cube will be 18 into 30 gram.
00:22
The temperature of water and temperature of ice is also given.
00:26
Specific heat capacity of water in solid and liquid form is.
00:30
Also given delta h vaporization of cf2 cl2 and delta h fuzin of ice is given here we can say that first the temperature of water will decrease from 22 degrees celsius to 0 degrees celsius for which there will be energy release and that energy release q1 will be given by the relation m cp delta t m is the mass cp is the specific heat capacity of water and delta t is changed in after that, there will be phase change from water to ice in that there will be q2 heat release, it will be equal to moles into delta h vaporization.
01:13
And then there will be decrease in temperature from 0 degrees celsius to minus 5 degrees celsius.
01:21
That q3 energy or heat will be given by the relation m, cp, delta t.
01:29
Here, cp is the specific heat capacity of ice.
01:33
We can substitute the values for q1 heat release in this manner.
01:38
Now we will eliminate the common units.
01:40
Gram will be cancelled from gram.
01:41
Degree celsius will be cancelled from degree celsius.
01:44
And on solving this, we are getting the q1 value minus 49740.
01:52
We can convert it into kilojoule by dividing this value by 1000.
01:56
On doing so, we are getting minus 49.
01:59
7 4 kilojoule.
02:02
Now we can substitute the values for q2 heat release.
02:05
It will be equal to moles into delta h vaporization...